diff --git a/http2/http2_structures_test.cc b/http2/http2_structures_test.cc
new file mode 100644
index 0000000..30ebb36
--- /dev/null
+++ b/http2/http2_structures_test.cc
@@ -0,0 +1,537 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/third_party/quiche/src/http2/http2_structures.h"
+
+// Tests are focused on Http2FrameHeader because it has by far the most
+// methods of any of the structures.
+// Note that EXPECT.*DEATH tests are slow (a fork is probably involved).
+
+// And in case you're wondering, yes, these are ridiculously thorough tests,
+// but believe it or not, I've found stupid bugs this way.
+
+#include <memory>
+#include <ostream>
+#include <sstream>
+#include <tuple>
+#include <type_traits>
+#include <vector>
+
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "net/third_party/quiche/src/http2/http2_structures_test_util.h"
+#include "net/third_party/quiche/src/http2/platform/api/http2_string_utils.h"
+#include "net/third_party/quiche/src/http2/platform/api/http2_test_helpers.h"
+#include "net/third_party/quiche/src/http2/test_tools/http2_random.h"
+
+using ::testing::AssertionResult;
+using ::testing::AssertionSuccess;
+using ::testing::Combine;
+using ::testing::HasSubstr;
+using ::testing::MatchesRegex;
+using ::testing::Not;
+using ::testing::Values;
+using ::testing::ValuesIn;
+
+namespace http2 {
+namespace test {
+namespace {
+
+template <typename E>
+E IncrementEnum(E e) {
+  using I = typename std::underlying_type<E>::type;
+  return static_cast<E>(1 + static_cast<I>(e));
+}
+
+template <class T>
+AssertionResult VerifyRandomCalls() {
+  T t1;
+  Http2Random seq1;
+  Randomize(&t1, &seq1);
+
+  T t2;
+  Http2Random seq2(seq1.Key());
+  Randomize(&t2, &seq2);
+
+  // The two Randomize calls should have made the same number of calls into
+  // the Http2Random implementations.
+  VERIFY_EQ(seq1.Rand64(), seq2.Rand64());
+
+  // And because Http2Random implementation is returning the same sequence, and
+  // Randomize should have been consistent in applying those results, the two
+  // Ts should have the same value.
+  VERIFY_EQ(t1, t2);
+
+  Randomize(&t2, &seq2);
+  VERIFY_NE(t1, t2);
+
+  Randomize(&t1, &seq1);
+  VERIFY_EQ(t1, t2);
+
+  VERIFY_EQ(seq1.Rand64(), seq2.Rand64());
+
+  return AssertionSuccess();
+}
+
+#if GTEST_HAS_DEATH_TEST && !defined(NDEBUG)
+std::vector<Http2FrameType> ValidFrameTypes() {
+  std::vector<Http2FrameType> valid_types{Http2FrameType::DATA};
+  while (valid_types.back() != Http2FrameType::ALTSVC) {
+    valid_types.push_back(IncrementEnum(valid_types.back()));
+  }
+  return valid_types;
+}
+#endif  // GTEST_HAS_DEATH_TEST && !defined(NDEBUG)
+
+TEST(Http2FrameHeaderTest, Constructor) {
+  Http2Random random;
+  uint8_t frame_type = 0;
+  do {
+    // Only the payload length is DCHECK'd in the constructor, so we need to
+    // make sure it is a "uint24".
+    uint32_t payload_length = random.Rand32() & 0xffffff;
+    Http2FrameType type = static_cast<Http2FrameType>(frame_type);
+    uint8_t flags = random.Rand8();
+    uint32_t stream_id = random.Rand32();
+
+    Http2FrameHeader v(payload_length, type, flags, stream_id);
+
+    EXPECT_EQ(payload_length, v.payload_length);
+    EXPECT_EQ(type, v.type);
+    EXPECT_EQ(flags, v.flags);
+    EXPECT_EQ(stream_id, v.stream_id);
+  } while (frame_type++ == 255);
+
+#if GTEST_HAS_DEATH_TEST && !defined(NDEBUG)
+  EXPECT_DEBUG_DEATH(Http2FrameHeader(0x01000000, Http2FrameType::DATA, 0, 1),
+                     "payload_length");
+#endif  // GTEST_HAS_DEATH_TEST && !defined(NDEBUG)
+}
+
+TEST(Http2FrameHeaderTest, Eq) {
+  Http2Random random;
+  uint32_t payload_length = random.Rand32() & 0xffffff;
+  Http2FrameType type = static_cast<Http2FrameType>(random.Rand8());
+
+  uint8_t flags = random.Rand8();
+  uint32_t stream_id = random.Rand32();
+
+  Http2FrameHeader v(payload_length, type, flags, stream_id);
+
+  EXPECT_EQ(payload_length, v.payload_length);
+  EXPECT_EQ(type, v.type);
+  EXPECT_EQ(flags, v.flags);
+  EXPECT_EQ(stream_id, v.stream_id);
+
+  Http2FrameHeader u(0, type, ~flags, stream_id);
+
+  EXPECT_NE(u, v);
+  EXPECT_NE(v, u);
+  EXPECT_FALSE(u == v);
+  EXPECT_FALSE(v == u);
+  EXPECT_TRUE(u != v);
+  EXPECT_TRUE(v != u);
+
+  u = v;
+
+  EXPECT_EQ(u, v);
+  EXPECT_EQ(v, u);
+  EXPECT_TRUE(u == v);
+  EXPECT_TRUE(v == u);
+  EXPECT_FALSE(u != v);
+  EXPECT_FALSE(v != u);
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2FrameHeader>());
+}
+
+#if GTEST_HAS_DEATH_TEST && !defined(NDEBUG)
+// The tests of the valid frame types include EXPECT_DEBUG_DEATH, which is
+// quite slow, so using value parameterized tests in order to allow sharding.
+class Http2FrameHeaderTypeAndFlagTest
+    : public ::testing::TestWithParam<
+          std::tuple<Http2FrameType, Http2FrameFlag>> {
+ protected:
+  Http2FrameHeaderTypeAndFlagTest()
+      : type_(std::get<0>(GetParam())), flags_(std::get<1>(GetParam())) {
+    LOG(INFO) << "Frame type: " << type_;
+    LOG(INFO) << "Frame flags: " << Http2FrameFlagsToString(type_, flags_);
+  }
+
+  const Http2FrameType type_;
+  const Http2FrameFlag flags_;
+};
+
+class IsEndStreamTest : public Http2FrameHeaderTypeAndFlagTest {};
+INSTANTIATE_TEST_CASE_P(IsEndStream,
+                        IsEndStreamTest,
+                        Combine(ValuesIn(ValidFrameTypes()),
+                                Values(~Http2FrameFlag::END_STREAM, 0xff)));
+TEST_P(IsEndStreamTest, IsEndStream) {
+  const bool is_set =
+      (flags_ & Http2FrameFlag::END_STREAM) == Http2FrameFlag::END_STREAM;
+  Http2String flags_string;
+  Http2FrameHeader v(0, type_, flags_, 0);
+  switch (type_) {
+    case Http2FrameType::DATA:
+    case Http2FrameType::HEADERS:
+      EXPECT_EQ(is_set, v.IsEndStream()) << v;
+      flags_string = v.FlagsToString();
+      if (is_set) {
+        EXPECT_THAT(flags_string, MatchesRegex(".*\\|?END_STREAM\\|.*"));
+      } else {
+        EXPECT_THAT(flags_string, Not(HasSubstr("END_STREAM")));
+      }
+      v.RetainFlags(Http2FrameFlag::END_STREAM);
+      EXPECT_EQ(is_set, v.IsEndStream()) << v;
+      {
+        std::stringstream s;
+        s << v;
+        EXPECT_EQ(v.ToString(), s.str());
+        if (is_set) {
+          EXPECT_THAT(s.str(), HasSubstr("flags=END_STREAM,"));
+        } else {
+          EXPECT_THAT(s.str(), HasSubstr("flags=,"));
+        }
+      }
+      break;
+    default:
+      EXPECT_DEBUG_DEATH(v.IsEndStream(), "DATA.*HEADERS") << v;
+  }
+}
+
+class IsACKTest : public Http2FrameHeaderTypeAndFlagTest {};
+INSTANTIATE_TEST_CASE_P(IsAck,
+                        IsACKTest,
+                        Combine(ValuesIn(ValidFrameTypes()),
+                                Values(~Http2FrameFlag::ACK, 0xff)));
+TEST_P(IsACKTest, IsAck) {
+  const bool is_set = (flags_ & Http2FrameFlag::ACK) == Http2FrameFlag::ACK;
+  Http2String flags_string;
+  Http2FrameHeader v(0, type_, flags_, 0);
+  switch (type_) {
+    case Http2FrameType::SETTINGS:
+    case Http2FrameType::PING:
+      EXPECT_EQ(is_set, v.IsAck()) << v;
+      flags_string = v.FlagsToString();
+      if (is_set) {
+        EXPECT_THAT(flags_string, MatchesRegex(".*\\|?ACK\\|.*"));
+      } else {
+        EXPECT_THAT(flags_string, Not(HasSubstr("ACK")));
+      }
+      v.RetainFlags(Http2FrameFlag::ACK);
+      EXPECT_EQ(is_set, v.IsAck()) << v;
+      {
+        std::stringstream s;
+        s << v;
+        EXPECT_EQ(v.ToString(), s.str());
+        if (is_set) {
+          EXPECT_THAT(s.str(), HasSubstr("flags=ACK,"));
+        } else {
+          EXPECT_THAT(s.str(), HasSubstr("flags=,"));
+        }
+      }
+      break;
+    default:
+      EXPECT_DEBUG_DEATH(v.IsAck(), "SETTINGS.*PING") << v;
+  }
+}
+
+class IsEndHeadersTest : public Http2FrameHeaderTypeAndFlagTest {};
+INSTANTIATE_TEST_CASE_P(IsEndHeaders,
+                        IsEndHeadersTest,
+                        Combine(ValuesIn(ValidFrameTypes()),
+                                Values(~Http2FrameFlag::END_HEADERS, 0xff)));
+TEST_P(IsEndHeadersTest, IsEndHeaders) {
+  const bool is_set =
+      (flags_ & Http2FrameFlag::END_HEADERS) == Http2FrameFlag::END_HEADERS;
+  Http2String flags_string;
+  Http2FrameHeader v(0, type_, flags_, 0);
+  switch (type_) {
+    case Http2FrameType::HEADERS:
+    case Http2FrameType::PUSH_PROMISE:
+    case Http2FrameType::CONTINUATION:
+      EXPECT_EQ(is_set, v.IsEndHeaders()) << v;
+      flags_string = v.FlagsToString();
+      if (is_set) {
+        EXPECT_THAT(flags_string, MatchesRegex(".*\\|?END_HEADERS\\|.*"));
+      } else {
+        EXPECT_THAT(flags_string, Not(HasSubstr("END_HEADERS")));
+      }
+      v.RetainFlags(Http2FrameFlag::END_HEADERS);
+      EXPECT_EQ(is_set, v.IsEndHeaders()) << v;
+      {
+        std::stringstream s;
+        s << v;
+        EXPECT_EQ(v.ToString(), s.str());
+        if (is_set) {
+          EXPECT_THAT(s.str(), HasSubstr("flags=END_HEADERS,"));
+        } else {
+          EXPECT_THAT(s.str(), HasSubstr("flags=,"));
+        }
+      }
+      break;
+    default:
+      EXPECT_DEBUG_DEATH(v.IsEndHeaders(),
+                         "HEADERS.*PUSH_PROMISE.*CONTINUATION")
+          << v;
+  }
+}
+
+class IsPaddedTest : public Http2FrameHeaderTypeAndFlagTest {};
+INSTANTIATE_TEST_CASE_P(IsPadded,
+                        IsPaddedTest,
+                        Combine(ValuesIn(ValidFrameTypes()),
+                                Values(~Http2FrameFlag::PADDED, 0xff)));
+TEST_P(IsPaddedTest, IsPadded) {
+  const bool is_set =
+      (flags_ & Http2FrameFlag::PADDED) == Http2FrameFlag::PADDED;
+  Http2String flags_string;
+  Http2FrameHeader v(0, type_, flags_, 0);
+  switch (type_) {
+    case Http2FrameType::DATA:
+    case Http2FrameType::HEADERS:
+    case Http2FrameType::PUSH_PROMISE:
+      EXPECT_EQ(is_set, v.IsPadded()) << v;
+      flags_string = v.FlagsToString();
+      if (is_set) {
+        EXPECT_THAT(flags_string, MatchesRegex(".*\\|?PADDED\\|.*"));
+      } else {
+        EXPECT_THAT(flags_string, Not(HasSubstr("PADDED")));
+      }
+      v.RetainFlags(Http2FrameFlag::PADDED);
+      EXPECT_EQ(is_set, v.IsPadded()) << v;
+      {
+        std::stringstream s;
+        s << v;
+        EXPECT_EQ(v.ToString(), s.str());
+        if (is_set) {
+          EXPECT_THAT(s.str(), HasSubstr("flags=PADDED,"));
+        } else {
+          EXPECT_THAT(s.str(), HasSubstr("flags=,"));
+        }
+      }
+      break;
+    default:
+      EXPECT_DEBUG_DEATH(v.IsPadded(), "DATA.*HEADERS.*PUSH_PROMISE") << v;
+  }
+}
+
+class HasPriorityTest : public Http2FrameHeaderTypeAndFlagTest {};
+INSTANTIATE_TEST_CASE_P(HasPriority,
+                        HasPriorityTest,
+                        Combine(ValuesIn(ValidFrameTypes()),
+                                Values(~Http2FrameFlag::PRIORITY, 0xff)));
+TEST_P(HasPriorityTest, HasPriority) {
+  const bool is_set =
+      (flags_ & Http2FrameFlag::PRIORITY) == Http2FrameFlag::PRIORITY;
+  Http2String flags_string;
+  Http2FrameHeader v(0, type_, flags_, 0);
+  switch (type_) {
+    case Http2FrameType::HEADERS:
+      EXPECT_EQ(is_set, v.HasPriority()) << v;
+      flags_string = v.FlagsToString();
+      if (is_set) {
+        EXPECT_THAT(flags_string, MatchesRegex(".*\\|?PRIORITY\\|.*"));
+      } else {
+        EXPECT_THAT(flags_string, Not(HasSubstr("PRIORITY")));
+      }
+      v.RetainFlags(Http2FrameFlag::PRIORITY);
+      EXPECT_EQ(is_set, v.HasPriority()) << v;
+      {
+        std::stringstream s;
+        s << v;
+        EXPECT_EQ(v.ToString(), s.str());
+        if (is_set) {
+          EXPECT_THAT(s.str(), HasSubstr("flags=PRIORITY,"));
+        } else {
+          EXPECT_THAT(s.str(), HasSubstr("flags=,"));
+        }
+      }
+      break;
+    default:
+      EXPECT_DEBUG_DEATH(v.HasPriority(), "HEADERS") << v;
+  }
+}
+
+TEST(Http2PriorityFieldsTest, Constructor) {
+  Http2Random random;
+  uint32_t stream_dependency = random.Rand32() & StreamIdMask();
+  uint32_t weight = 1 + random.Rand8();
+  bool is_exclusive = random.OneIn(2);
+
+  Http2PriorityFields v(stream_dependency, weight, is_exclusive);
+
+  EXPECT_EQ(stream_dependency, v.stream_dependency);
+  EXPECT_EQ(weight, v.weight);
+  EXPECT_EQ(is_exclusive, v.is_exclusive);
+
+  // The high-bit must not be set on the stream id.
+  EXPECT_DEBUG_DEATH(
+      Http2PriorityFields(stream_dependency | 0x80000000, weight, is_exclusive),
+      "31-bit");
+
+  // The weight must be in the range 1-256.
+  EXPECT_DEBUG_DEATH(Http2PriorityFields(stream_dependency, 0, is_exclusive),
+                     "too small");
+  EXPECT_DEBUG_DEATH(
+      Http2PriorityFields(stream_dependency, weight + 256, is_exclusive),
+      "too large");
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2PriorityFields>());
+}
+#endif  // GTEST_HAS_DEATH_TEST && !defined(NDEBUG)
+
+TEST(Http2RstStreamFieldsTest, IsSupported) {
+  Http2RstStreamFields v{Http2ErrorCode::HTTP2_NO_ERROR};
+  EXPECT_TRUE(v.IsSupportedErrorCode()) << v;
+
+  Http2RstStreamFields u{static_cast<Http2ErrorCode>(~0)};
+  EXPECT_FALSE(u.IsSupportedErrorCode()) << v;
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2RstStreamFields>());
+}
+
+TEST(Http2SettingFieldsTest, Misc) {
+  Http2Random random;
+  Http2SettingsParameter parameter =
+      static_cast<Http2SettingsParameter>(random.Rand16());
+  uint32_t value = random.Rand32();
+
+  Http2SettingFields v(parameter, value);
+
+  EXPECT_EQ(v, v);
+  EXPECT_EQ(parameter, v.parameter);
+  EXPECT_EQ(value, v.value);
+
+  if (static_cast<uint16_t>(parameter) < 7) {
+    EXPECT_TRUE(v.IsSupportedParameter()) << v;
+  } else {
+    EXPECT_FALSE(v.IsSupportedParameter()) << v;
+  }
+
+  Http2SettingFields u(parameter, ~value);
+  EXPECT_NE(v, u);
+  EXPECT_EQ(v.parameter, u.parameter);
+  EXPECT_NE(v.value, u.value);
+
+  Http2SettingFields w(IncrementEnum(parameter), value);
+  EXPECT_NE(v, w);
+  EXPECT_NE(v.parameter, w.parameter);
+  EXPECT_EQ(v.value, w.value);
+
+  Http2SettingFields x(Http2SettingsParameter::MAX_FRAME_SIZE, 123);
+  std::stringstream s;
+  s << x;
+  EXPECT_EQ("parameter=MAX_FRAME_SIZE, value=123", s.str());
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2SettingFields>());
+}
+
+TEST(Http2PushPromiseTest, Misc) {
+  Http2Random random;
+  uint32_t promised_stream_id = random.Rand32() & StreamIdMask();
+
+  Http2PushPromiseFields v{promised_stream_id};
+  EXPECT_EQ(promised_stream_id, v.promised_stream_id);
+  EXPECT_EQ(v, v);
+
+  std::stringstream s;
+  s << v;
+  EXPECT_EQ(Http2StrCat("promised_stream_id=", promised_stream_id), s.str());
+
+  // High-bit is reserved, but not used, so we can set it.
+  promised_stream_id |= 0x80000000;
+  Http2PushPromiseFields w{promised_stream_id};
+  EXPECT_EQ(w, w);
+  EXPECT_NE(v, w);
+
+  v.promised_stream_id = promised_stream_id;
+  EXPECT_EQ(v, w);
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2PushPromiseFields>());
+}
+
+TEST(Http2PingFieldsTest, Misc) {
+  Http2PingFields v{{'8', ' ', 'b', 'y', 't', 'e', 's', '\0'}};
+  std::stringstream s;
+  s << v;
+  EXPECT_EQ("opaque_bytes=0x3820627974657300", s.str());
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2PingFields>());
+}
+
+TEST(Http2GoAwayFieldsTest, Misc) {
+  Http2Random random;
+  uint32_t last_stream_id = random.Rand32() & StreamIdMask();
+  Http2ErrorCode error_code = static_cast<Http2ErrorCode>(random.Rand32());
+
+  Http2GoAwayFields v(last_stream_id, error_code);
+  EXPECT_EQ(v, v);
+  EXPECT_EQ(last_stream_id, v.last_stream_id);
+  EXPECT_EQ(error_code, v.error_code);
+
+  if (static_cast<uint32_t>(error_code) < 14) {
+    EXPECT_TRUE(v.IsSupportedErrorCode()) << v;
+  } else {
+    EXPECT_FALSE(v.IsSupportedErrorCode()) << v;
+  }
+
+  Http2GoAwayFields u(~last_stream_id, error_code);
+  EXPECT_NE(v, u);
+  EXPECT_NE(v.last_stream_id, u.last_stream_id);
+  EXPECT_EQ(v.error_code, u.error_code);
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2GoAwayFields>());
+}
+
+TEST(Http2WindowUpdateTest, Misc) {
+  Http2Random random;
+  uint32_t window_size_increment = random.Rand32() & UInt31Mask();
+
+  Http2WindowUpdateFields v{window_size_increment};
+  EXPECT_EQ(window_size_increment, v.window_size_increment);
+  EXPECT_EQ(v, v);
+
+  std::stringstream s;
+  s << v;
+  EXPECT_EQ(Http2StrCat("window_size_increment=", window_size_increment),
+            s.str());
+
+  // High-bit is reserved, but not used, so we can set it.
+  window_size_increment |= 0x80000000;
+  Http2WindowUpdateFields w{window_size_increment};
+  EXPECT_EQ(w, w);
+  EXPECT_NE(v, w);
+
+  v.window_size_increment = window_size_increment;
+  EXPECT_EQ(v, w);
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2WindowUpdateFields>());
+}
+
+TEST(Http2AltSvcTest, Misc) {
+  Http2Random random;
+  uint16_t origin_length = random.Rand16();
+
+  Http2AltSvcFields v{origin_length};
+  EXPECT_EQ(origin_length, v.origin_length);
+  EXPECT_EQ(v, v);
+
+  std::stringstream s;
+  s << v;
+  EXPECT_EQ(Http2StrCat("origin_length=", origin_length), s.str());
+
+  Http2AltSvcFields w{++origin_length};
+  EXPECT_EQ(w, w);
+  EXPECT_NE(v, w);
+
+  v.origin_length = w.origin_length;
+  EXPECT_EQ(v, w);
+
+  EXPECT_TRUE(VerifyRandomCalls<Http2AltSvcFields>());
+}
+
+}  // namespace
+}  // namespace test
+}  // namespace http2